Brothers and community leaders David and Manuel Macias were born in Zacatecas, Mexico, in 1885 and 1890, respectively. David Macias, an accomplished musician, had originally planned on becoming a priest. But after the Mexican Revolution derailed his plan, he began working as a chemist for an American mining company with operations in Mexico. After several business trips that took him north of the border, he decided to permanently emigrate to the U.S. Among the first Mexicans to live in the Quad Cities, he arrived in Bettendorf in 1914, and found work at the Bettendorf Car Company. Manuel Macias did not immediately accompany his brother to the U.S. He married Guadalupe Perez, also from Zacatecas, in 1912 and joined David Macias in Bettendorf in 1915.

During World War I, the Macias brothers went to Juarez, Mexico, to recruit Mexicans to work in the Bettendorf Company foundries in order to help fill the labor shortage caused by U.S. entry into the war. The brothers served as leaders to these recent arrivals to the Mexican barrio known as Holy City adjacent to the Bettendorf Company. David Macias spoke English fluently, and acted as a translator and "go-between" for those who did not.

In 1918, the brothers learned of a community of Mexicans living nearby in a barrio in Silvis, Illinois, called La Yarda. Manuel Macias volunteered to teach music to local adults and children, and converted two railroad boxcars into a rehearsal hall and storage space for band instruments. In 1927, the Silvis rehearsal hall became Our Lady of Guadalupe Church, a place of worship as well as a community gathering point for Mexicans on both sides of the Mississippi River.